A specialization of geographical thing and physical surface. Each instance of geographical region is a tangible spatial region that includes some piece of the surface of a planet (usually Earth), and may be represented on a map of the planet. This includes purely topographical regions like mountains and underwater spaces, places defined by demographics (e.g. language areas) and territory otherwise demarcated (e.g. TimeZones). In dualist geopolitical contexts (see Dualist Geopolitical Mt, instances of political entity are also considered to be instances of geographical region.

In all cases the region in question must contain some tangible component with which it is possible to make physical contact. The instances of geographical region contrast in this respect with the instances of intangible geographical thing, which are wholly intangible.

Examples of geographical region include Rocky Mountain state, the Australia, the Sinai Peninsula, and -- in dualist geopolitical contexts -- Yale University and Pittsburgh. Some important types of regions are represented by the sub-collections language area, time zone, postal code region, ecological region, construction site, and -- in dualist geopolitical contexts -- political entity. No instances of geographical region are wholly indoor locations.